Height of the ozonehole over the brazilian Antarctic station
Abstract
The vertical ozone concentration has been measured using Electro-Chemical Concentration, ECC ozonesondes, launched on balloons at the Brazilian Antarctic station, on King George Island (62.1° S; 58.4° W), during field campaigns in 2003 and 1999. The launching technique and procedures are the same as those used for the Natal, Brazil, sounding program, in operation for many years. The concentration of ozone is measured from the ground to heights of about 30-34 km. During springtime, a well developed ozonehole has been present over the station. The height of the ozone minimum concentration, during the presence of the ozonehole, is remarkably stable and constant from day to day, at about 16 km, in the lower stratosphere. From a sonde set of 11 units launched in 2003, the average height of minimum ozone is 16.9 ± 1.0 km. The comparison of the total ozone content measured by the ozonesondes with the Total Ozone Mapping Spectrometer, TOMS is expressed by the percentage difference 100*(Sonde-Toms)/Sonde = 5.3 ± 3.1%. A Brewer spectrophotometer that operates from the ground has also been used during the campaign, giving a percentage difference of 3.9 ± 2.4 %. These parameters become for the earlier 1999 Spring period 16.3 ± 1.1 km, and 3.8 ± 2.4 % respectively (no Brewer Spectrophotometer data in 1999). In terms of the UV-B index, higher values were seen during 2003: on two occasions the Index passed the level of 9; which is larger than values observed on any previous campaign at the site. During the end of September and the beginning of October the index running mean reached 6, while during the 2001 equivalent period the value was about 5.
- Publication:
-
35th COSPAR Scientific Assembly
- Pub Date:
- 2004
- Bibcode:
- 2004cosp...35.2716K